field test unit no 001 "model T"

[moodz]

This new design is fantastic as a thought exercise how would its power be increased, in this design is the coil energized with 17V ?. Ignoring diminishing returns and battery weight etc is increasing the power as simple as increasing the voltage across the coil ?.

Basically yes ....I have a design running on the bench that gets more than 20 amps peak in the coil but draws around 70 ma from a 48 volt supply ( 4 x 12 volt lipo battery ). Resistance must be very low.

Moodz

[hdphilip]

hello

I was thinking about building the UNIPI_DS_v320_R003 frontend, my question is..

where does the 'GROUND BALANCE IN' and the "DESCRIM BALANCE IN" connect to on the
cpu board, will this work with the 4012 cpu board?

looks like a fun project!!!!

Philip

[moodz]

hello

I was thinking about building the UNIPI_DS_v320_R003 frontend, my question is..

where does the 'GROUND BALANCE IN' and the "DESCRIM BALANCE IN" connect to on the
cpu board, will this work with the 4012 cpu board?

looks like a fun project!!!!

Philip

Hi Philip ... the ground / descrim balance comes from one of the UNIPI PWM outputs ( see UNIPI chip ). This is a PWM signal and is adjusted from the LCD menu.

You should build up UNIPI chip / LCD controller board first then build the frontend. Note that these circuits are for experimentation mainly ...they are not a complete systemm yet.

moodz

[hdphilip]

moodz,

I'm going to build the 4012 first, then experiment with the different front ends, I'm making the PCB now. I do have the 4011 chip also.

I found some software, "PICPgm development programmer 1.6.4.2" that I'll try to use to program the dsPIC30f4012 with the jdm programmer.

Philip

[Midas]

moodz,

I'm going to build the 4012 first, then experiment with the different front ends, I'm making the PCB now. I do have the 4011 chip also.

I found some software, "PICPgm development programmer 1.6.4.2" that I'll try to use to program the dsPIC30f4012 with the jdm programmer.

Philip

You'll need the increasingly rare, 'real' serial port. Most if not all USB or PCI adapator serial ports don't work with JDM style programmers. Manufacturers of these devices have very little respect for the RS232 standard... 5v.. 12v.. what's the difference..

[hdphilip]

hello midas,

lol, i was thinking that, i have a old computer with that, also i was thinking about doing it
in circuit, because of the power requirements.

Which front end have you had good luck experimenting with?

Philip

[Midas]

hello midas,

lol, i was thinking that, i have a old computer with that, also i was thinking about doing it
in circuit, because of the power requirements.

Which front end have you had good luck experimenting with?

Philip

Hi Phil,

Yeah I have a second machine pretty much exclusively for that purpose that I hook into using a program called tightVNC. Its good, saves having to keep swapping monitors\keyboards and mices all the time. I've not managed to build either of them... too much procrastination.

Midas

[hdphilip]

rev 003 front end pcb

so far so good on the front end pcb project, can't wait til i start testing it!

I decided to make the "series blocking fet on it's own plug in board for testing, right now i'm going to just stert with the diodes first, then I can just change board to see what the performance differences are.

the trimpot (next to the voltage regulator) is inserted between the gnd and the 7805 gnd tab, set to about 5.3 volts

for some reason, i'm still having a few issues with the rotory encoder,

Philip

[6666]

Good job Philip
what method did you use to make the PCB ?

[hdphilip]

6666,

I used the negative photo resist,

MG chemicial 416 DFR

i make the transparency on my laser printer

making pcb's pretty easy, it just takes a few tries to get the exposure
right, i find 6 minutes with a "black light" at 12 inches works,

here's the board before i etched it.

the two boards on the side of it are for input blocking fet ideas

Philip

[hdphilip]

rotary encoder

Rotary encoder problem solved!

(forgot the pull up resistors)

Philip

[hdphilip]

Here's a few pictures of my current progress
first picture is no target
second picture copper pcb laying on the coil
third picture is a metal cover also laying on the coil

the scope leads were attached to L1 and L2 referenced to coil center tap.

next, the blocking fet setup.

Philip

[satdaveuk]

Thats remarkable you all have come along way on your project.
Ive ordered some ics lcd display , and a programer so i can have a go complete novis to programing ics but firmly stand by its better to jump in at the deepend then swim for shallower waters.
I been following this forum for 2 weeks now certainly a different kettle of fish to other projects ive been involved in.
Take my hat off to you all.

Regards

[6666]

Good work


MG chemical 416 DFR been discontinued, rats

[hdphilip]

6666

yea it figures, when i seen that, i ordered another roll, i seen some similiar products on ebay, might be worth a try.

Philip